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Possible Dead Battery?

ThatGuyBigNick

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Morning everyone,

Went to start the truck yesterday and it wouldn’t turn over. I’m assuming the battery is dead, but I’m not sure how to check if I need both batteries or just one. Any help or tips or previous threads would be amazing.

Here is a quick video of what happens when I try to start it.
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ShadowsPapa

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Assuming because you have a 2020, it's past the 3/36 warranty, so won't talk "take it to a dealer".

However, because it is a 2020, and the batteries could be (your vehicle build date unknown to us) 3 to 4 years old - I'd actually recommend both batteries be replaced - charging each with a good AGM capable charger before installation.
You have another choice - check to determine which one is misbehaving -
Pull the ground cable off the main battery (off the top of the IBS)
Pull the IBS (the intelligent battery sensor on the negative battery terminal) off and set it aside.
Disconnect the two black ground cables from each other.
You having a 2020 means that the top or cable with the smaller end is the one that goes to the aux battery negative, making this easier.
Anyway, charge the main battery with a good charger (10 amps or better, AGM charger) and let it go through all phases of charging.
After that is done, leave the charger's red or positive clamp on the main battery cable terminal because that also connects to the aux positive terminal through the PCR (won't get into that detail now)
Move the charger's negative lead or clamp to the end of the ground cable that goes to the aux battery. It's the black cable with the small end on a 2020.
Charge the aux battery like you did the main battery.
When done, check the voltage of each battery.
If possible, let it sit a few hours with the batteries disconnected, ground cables not touching anything. Then check voltage again. A good battery sitting with no load should still show about 12.8 volts.
If after a time either is down to 12.6 or lower, it's bad.
This isn't the best battery test in the world, but if it fails this, you know it's bad because a good battery will hold that full charge, maybe even higher - holding a surface charge for a couple of hours. A bad battery may drop quickly.
But a bad battery can also show high voltage but crash down as quick as any load is put on it. So this is a quicky test, not a "definitive" test.

I'm in my shop on a chromebook, don't have access to my photos on my server from here or I'd post a picture of how/where to connect to charge each battery this way.
You are also resetting the IBS as well in this process by having it disconnected while charging the batteries - giving everything a fresh start from the ground up.

I'd lean on both batteries being a 2020 - but it's your call, your money, your time. Batteries just don't last like they used to and 4 years is a pretty good life for these batteries.
 
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ThatGuyBigNick

ThatGuyBigNick

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Thank you for the very detailed reply. I don’t have a charger, so I guess I’ll be replacing.

I was thinking about deleting the start stop battery, will have to look into if I can get something before heading out to expo this weekend.
 

ShadowsPapa

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Thank you for the very detailed reply. I don’t have a charger, so I guess I’ll be replacing.

I was thinking about deleting the start stop battery, will have to look into if I can get something before heading out to expo this weekend.
If you replace - and don't have a charger, be sure where you buy from fully charges them. They've been sitting and won't be full and it will throw things out of whack as the IBS should be reset (by disconnecting from the battery and cables) for several seconds.
Don't install new batteries unless they have been fully charged first. And don't let them tell you "not necessary" - that will only prove they don't know the product they are selling.
Just sitting, batteries lose a charge.
Or - find a friend with a good AGM capable charger and have them do it.

In other words - one way or another you need a charger, or access to one or someone who will charge them and not argue that new batteries don't need it.
 

Dunks001

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@ShadowsPapa Thanks for the detailed post. I have a 2020 as well. Bought a Full River battery at expo haven't put it in yet. Would you suggest deleting the small starter battery? Thx
 

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ShadowsPapa

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@ShadowsPapa Thanks for the detailed post. I have a 2020 as well. Bought a Full River battery at expo haven't put it in yet. Would you suggest deleting the small starter battery? Thx
The small battery is the axillary battery, runs the "electronics", dash and cluster items during an ESS stop event.
Most never have problems with the small aux battery - it's your truck but I have no plans on removing or bypassing anything on mine, and left my 2020 electrically stock in that area as well.
 

Lost1wing

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Assuming because you have a 2020, it's past the 3/36 warranty, so won't talk "take it to a dealer".

However, because it is a 2020, and the batteries could be (your vehicle build date unknown to us) 3 to 4 years old - I'd actually recommend both batteries be replaced - charging each with a good AGM capable charger before installation.
You have another choice - check to determine which one is misbehaving -
Pull the ground cable off the main battery (off the top of the IBS)
Pull the IBS (the intelligent battery sensor on the negative battery terminal) off and set it aside.
Disconnect the two black ground cables from each other.
You having a 2020 means that the top or cable with the smaller end is the one that goes to the aux battery negative, making this easier.
Anyway, charge the main battery with a good charger (10 amps or better, AGM charger) and let it go through all phases of charging.
After that is done, leave the charger's red or positive clamp on the main battery cable terminal because that also connects to the aux positive terminal through the PCR (won't get into that detail now)
Move the charger's negative lead or clamp to the end of the ground cable that goes to the aux battery. It's the black cable with the small end on a 2020.
Charge the aux battery like you did the main battery.
When done, check the voltage of each battery.
If possible, let it sit a few hours with the batteries disconnected, ground cables not touching anything. Then check voltage again. A good battery sitting with no load should still show about 12.8 volts.
If after a time either is down to 12.6 or lower, it's bad.
This isn't the best battery test in the world, but if it fails this, you know it's bad because a good battery will hold that full charge, maybe even higher - holding a surface charge for a couple of hours. A bad battery may drop quickly.
But a bad battery can also show high voltage but crash down as quick as any load is put on it. So this is a quicky test, not a "definitive" test.

I'm in my shop on a chromebook, don't have access to my photos on my server from here or I'd post a picture of how/where to connect to charge each battery this way.
You are also resetting the IBS as well in this process by having it disconnected while charging the batteries - giving everything a fresh start from the ground up.

I'd lean on both batteries being a 2020 - but it's your call, your money, your time. Batteries just don't last like they used to and 4 years is a pretty good life for these batteries.
Yup!
 

Mr._Bill

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@ShadowsPapa Thanks for the detailed post. I have a 2020 as well. Bought a Full River battery at expo haven't put it in yet. Would you suggest deleting the small starter battery? Thx
The purpose of the Aux battery is to keep the computers stable during ESS events. During normal operation, they are paralleled together. If you are past warranty, and never use ESS, then removing it doesn't really matter. I prefer to leave it intact. Just be careful with the battery cables so that the high Amp fuse array doesn't get blown.
 
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ThatGuyBigNick

ThatGuyBigNick

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If you replace - and don't have a charger, be sure where you buy from fully charges them. They've been sitting and won't be full and it will throw things out of whack as the IBS should be reset (by disconnecting from the battery and cables) for several seconds.
Don't install new batteries unless they have been fully charged first. And don't let them tell you "not necessary" - that will only prove they don't know the product they are selling.
Just sitting, batteries lose a charge.
Or - find a friend with a good AGM capable charger and have them do it.

In other words - one way or another you need a charger, or access to one or someone who will charge them and not argue that new batteries don't need it.
Thanks again for the help. It was so late by the time I got home last night that I had to just grab one off the shelf to get to work today. But, I do have a neighbor with a charger that is going to let me use it tonight once I get home. So fingers crossed one day won’t hurt too bad.
 

ShadowsPapa

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Thanks again for the help. It was so late by the time I got home last night that I had to just grab one off the shelf to get to work today. But, I do have a neighbor with a charger that is going to let me use it tonight once I get home. So fingers crossed one day won’t hurt too bad.
You should be fine. If you have time, try to charge both batteries - full charge.
In any case, if you charge the main battery, pull the IBS off the top of the main battery, disconnect it from the ground cables and let it sit while charging. That will reset the IBS and more closely match a charged main battery.
But from then on, if you simply want to charge the battery or run a battery tender or maintainer on it, do that through the IBS by connecting to the top of the IBS where the cables connect and not below it on the battery terminal.

I suspect you'll be fine.
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